I have tried, but could never get very excited about the games here at Rocket Spanish. They seem pretty primitive, reminding me a lot of Pong. Who here remembers Pong?
Anyway, there is so much else out there to use for games or flashcards that it is not an issue to me. For example, I use Quizlet to study and learn verbs. I think that learning a new language takes a strategy that includes learning from a structured program like RS, but also requires reading, writing, games, flashcards, etc. etc. etc. I doubt that RS or any other provider could design an all inclusive program that would work best for every learner.